Spot check monitor credit system

ABSTRACT

A spot check credit system advantageously includes various embodiments for obtaining authorization or payment for each measurement, groups of measurements, times of measurement or the like. In an embodiment, the system utilizes a server that communicates web pages over a computer network. In an embodiment, the system utilizes a digital communication device such as a photocommunicative key.

PRIORITY CLAIM TO RELATED PROVISIONAL APPLICATIONS

The present application claims priority benefit under 35 U.S.C. §119(e)to U.S. Provisional Patent Application Ser. No. 61/242,384, filed Sep.14, 2009, titled Medical Device Life Monitor, U.S. Provisional PatentApplication Ser. No. 61/242,792, filed Sep. 15, 2009, titled Spot CheckPulse CO-Oximetry; U.S. Provisional Patent Application Ser. No.61/352,361, filed Jun. 7, 2010, titled Spot Check Credit System; U.S.Provisional Patent Application Ser. No. 61/354,251, filed Jun. 13, 2010,titled Spot Check Credit System; and U.S. Provisional Patent ApplicationSer. No. 61/382,812, filed Sep. 14, 2010, titled Advanced Spot CheckMonitor; all of the aforementioned provisional applications are herebyincorporated by reference herein.

BACKGROUND OF THE INVENTION

Pulse oximetry is a widely accepted noninvasive procedure for measuringthe oxygen saturation level of arterial blood, an indicator of aperson's oxygen supply. A typical pulse oximetry system utilizes asensor applied to a patient tissue site. The sensor has emitters thattransmit optical radiation having red and infrared (IR) wavelengths intothe tissue site. A detector responds to the intensity of the opticalradiation after attenuation by pulsatile arterial blood flowing withinthe tissue site. Based on this response, a processor determinesmeasurements for oxygen saturation and pulse rate. In addition, a pulseoximeter may display a plethysmograph waveform, which is a visualizationof blood volume change within the illuminated tissue caused by thepulsatile arterial blood flow over time.

Pulse oximeters capable of reading through motion induced noise areavailable from Masimo Corporation (“Masimo”) of Irvine, Calif. Moreover,portable and other pulse oximeters capable of reading through motioninduced noise are disclosed in at least U.S. Pat. Nos. 6,770,028,6,658,276, 6,157,850, 6,002,952 5,769,785, and 5,758,644, which areassigned to Masimo and are incorporated by reference herein.Corresponding low noise sensors are also available from Masimo and aredisclosed in at least U.S. Pat. Nos. 6,985,764, 6,813,511, 6,792,300,6,256,523, 6,088,607, 5,782,757 and 5,638,818, which are assigned toMasimo and are incorporated by reference herein. Such reading throughmotion pulse oximeters and low noise sensors have gained rapidacceptance in a wide variety of medical applications, including surgicalwards, intensive care and neonatal units, general wards, home care,physical training, and virtually all types of monitoring scenarios.

Noninvasive blood parameter monitors capable of measuring bloodparameters in addition to SpO₂, such as HbCO, HbMet and total hemoglobin(Hbt) and corresponding multiple wavelength optical sensors are alsoavailable from Masimo. Noninvasive blood parameter monitors andcorresponding multiple wavelength optical sensors are described in atleast U.S. patent application Ser. No. 11/367,013, filed Mar. 1, 2006and entitled Multiple Wavelength Sensor Emitters and U.S. patentapplication Ser. No. 11/366,208, filed Mar. 1, 2006 and entitledNoninvasive Multi-Parameter Patient Monitor, both assigned to MasimoLaboratories, Irvine, Calif. (Masimo Labs) and both incorporated byreference herein.

Further, physiological monitoring systems that include low noise opticalsensors and pulse oximetry monitors, such as any of LNOP® adhesive orreusable sensors, SofTouch™ sensors, Hi-Fi Trauma™ or BIue™ sensors; andany of Radical®, SatShare®, Rad-9® Rad-5®, Rad-5v™ or PPO+® Masimo SET®pulse oximeters, are all available from Masimo. Physiological monitoringsystems including multiple wavelength sensors and correspondingnoninvasive blood parameter monitors, such as Rainbow® adhesive andreusable sensors and RAD-57™ and Radical-7™ monitors for measuring SpO₂,pulse rate, perfusion index, signal quality, HbCO and HbMet among otherparameters are also available from Masimo.

Unlike the foregoing traditional pulse oximeters, many monitoringenvironments, such as, for example, hospital, caregiver, fitness, homecare, self monitoring or the like, expense care on a consumption basis.For example, when a caregiver uses a disposable medical product, such asa needle, bandage, etc., the caregiver bills an amount associated withthe disposable product to the payor of the patient's care, whether thatbe a government entity, private entity, or the patient themselves. Inthe case of sophisticated electronic medical instruments, many sensorsthereof include disposable parts, and billing is similarly accomplishedby tracking use of that disposable part and associating its use with apayor of the patient's care.

SUMMARY OF THE INVENTION

However, many other monitoring devices may lack single use disposableparts or other straightforward mechanisms of accounting for device usewith a particular patient. Such difficulties are exacerbated when thecaregiver extends or would have to extend large resources to acquireand/or maintain such monitoring equipment.

Additionally, as monitors become more sophisticated and digital datasuch as demographic information, monitoring history including trending,or even information about what is being monitored becomes moreprevalent, storage of such digital data on specific devices may be amanner in which potentially sensitive information can remain moreconfidential, private or at least in better patient control.

Based on at least the foregoing, the present disclosure includessystems, apparatuses, methods and devices addressing these and othershortfalls of the prior art. In various embodiments, the disclosureherein includes a physiological measurement system has a sensor thattransmits optical radiation at a multiplicity of wavelengths other thanor including the red and infrared wavelengths utilized in pulseoximeters. The system also has a processor that determines the relativeconcentrations of blood constituents other than or in addition to HbO₂and Hb, such as carboxyhemoglobin (HbCO), methemoglobin (MetHb),fractional oxygen saturation, total hemaglobin (Hbt) and blood glucoseto name a few. Further, such a system may be combined with otherphysiological parameters such as noninvasive blood pressure (NIBP).

A spot check monitor is advantageously utilized in conjunction with aphysiological measurement system so as to provide a mechanism to informusers that a medical device, such as a sensor, has exceeded its designedservice length. The spot check monitor collects information that isspecific to each device including information that reflects that adevice falls below usage limits set by the manufacturer.

One aspect of a spot check credit system partitions the task ofdistributing sensor credits between a server functioning as a creditprovider and various clients functioning as credit requesters. Theserver and the clients communicate over a computer network. The serverruns a web server program so as to serve web pages to the clients. Theclients run web browsers so as to receive the web pages and access spotcheck credits.

Another aspect of a spot check credit system comprises a server thatcommunicates web pages over a computer network. A client is incommunications with the server and executes a web browser so as toreceive the web pages. A spot check credit request is relayed from theclient to the server via one of the web pages. The request specifies asensor ID and a number of credits to purchase. Each spot check creditenables a single measurement for a group of physiological parameters. Acredit file application executes on the server so as to generate acredit file in response to the spot check credit request. The creditfile is downloaded from the server to the client.

In various embodiments, the spot check credit system further comprises aphysiological monitor in communications with the sensor so as to performspot check measurements in conjunction with the sensor. The monitor isin communications with the client so as to download the spot checkcredit file. In an embodiment, the credit file comprises a file sequencecode indicating when the credit file was created relative to othercredit files, a file sensor ID identifying a sensor and a number ofpurchased spot check credits. The sensor has a memory that stores asensor ID identifying the sensor, a sequence code of the most recentcredit file used to add credits to the sensor and a number of remainingspot check credits that is decremented after each spot checkmeasurement. The memory is readable by the monitor so as to, determineeach of the sensor ID, the sequence code and the remaining spot checkcredits.

In other embodiments, the monitor has an interface that downloads thesensor memory and uploads credit file data when the sensor is pluggedinto the monitor. A monitor display shows the sensor ID, the sequencecode and the spot check credit number prior to a credit download. Aprocessor compares the credit file with the sensor memory so as toverify the sensor ID and the sequence code. The monitor communicateswith the client via at least one of a USB cable interconnecting themonitor and the client and a memory card, which the client and themonitor can be read from and write to. In an embodiment, the flashmemory card, such as a MicroSD card, is physically transferred betweenthe client and the monitor for uploads and downloads. The sequence codemay be a coordinated universal time (UTC) stamp.

Another aspect to a spot check credit system is a method comprising thesteps of specifying a sensor ID; requesting spot check credits for thespecified sensor; creating a credit file with a time stamp, the sensorID and the credits; and encrypting the credit file. The credit file maybe downloaded to a client from a server and retransmitted to a monitorconnected to the client. The retransmission may be directly via a cableconnected between the client and monitor or indirectly via a flashmemory card.

In various embodiments, the credit file is decrypted and a sensorattached to the monitor is read so as to verify its sensor ID matchesthe credit file sensor ID. The sensor is read to determine a sensor timestamp. The credit file time stamp is verified to be later than thesensor time stamp. The credit file credits are added to pre-existingsensor credits.

In other embodiments, a spot check measurement is performed, adecremented credit count is downloaded to the sensor. The spot checkresults are uploaded to the client. An email address is associated withthe spot check results. The results are uploaded to the server alongwith the email address. The spot check results are stored on a serverdatabase. Also, the spot check results are emailed from the server tothe given email address.

An aspect of a spot check monitor method is a reusable sensor attachedto a spot check monitor so as to upload sensor credits to the sensor. Inan embodiment, each sensor credit represents a quantum of currency. Themonitor reads the number of sensor credits and is enabled to make aphysiological measurement in conjunction with the sensor if the numberof sensor credits is greater than zero. After the measurement, thenumber of sensor credits is decremented. The spot check monitoringmethod provides a physiological monitor having a sensor port thatattaches a reusable sensor. An optical sensor attaches to the sensorport. At least one sensor credit is uploaded from the monitor to storein sensor memory. The sensor credit represents a quantum of currency.The monitor reads the sensor memory so as to determine the number ofsensor credits is at least one. The monitor then performs aphysiological measurement in conjunction with the sensor based upon aremaining sensor credit. The monitor decrements the sensor memorycorresponding with the physiological measurement. In various embodimentsdifferent buttons are pressed on the spot check monitor to measuredifferent variables. For example, one button starts a SpO2 measurementand another button starts a SPCO measurement.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a physiological measurement systemincorporating reusable sensor and spot check monitor embodiments;

FIG. 2 is a perspective view of disposable sensor embodiment for usewith a physiological measurement system;

FIG. 3 is a block diagram of a physiological measurement systemincorporating a spot check monitor;

FIG. 4 is a detailed block diagram of a physiological measurement systemembodiment wherein each board, cable or sensor portion can have presetmedical device life data that is updated with use;

FIG. 5 is a flowchart of a physiological measurement systemconfiguration process including spot check credits;

FIG. 6 is a flowchart of medical device spot check process;

FIG. 7 is a perspective view of another spot check instrumentembodiment, including a monitor and corresponding sensor;

FIGS. 8A-C are front, back perspective and bottom views, respectively,of a spot check monitor embodiment;

FIGS. 9A-D are screen shots illustrating the steps for making a spotcheck measurement;

FIG. 10 is a system diagram of a spot check credit system;

FIG. 11 is a functional flow diagram of a spot check credit process;

FIGS. 12A-B are a conceptual view of a credit file and a state diagramof a credit file download to a spot check monitor;

FIGS. 13A-B are spot check monitor screen shots illustrating a sensorcredit download via USB cable;

FIG. 14 is a hierarchical page diagram of a spot check credit website;

FIGS. 15-19 are illustrations of spot check credit website pages;

FIG. 15A is a sales manager welcome page;

FIG. 15B is a sales representative welcome page;

FIG. 15C is a customer welcome page;

FIG. 15D is an administrator welcome page;

FIGS. 16A-B are sales rep management pages for the sales manager;

FIGS. 17A-C are customer and credit management pages for the salesrepresentatives;

FIGS. 18A-B are detailed equipment management and credit download pagesfor the sales representatives; and

FIGS. 19A-D are detailed credit, equipment, software update and techsupport pages for the customers.

FIG. 20 is an exemplary perspective view of an embodiment of a patientmonitor or physiological measurement system including a monitor, asensor, and a photocommunicative key configured to communicate with themonitor through the sensor.

FIGS. 21A-D are simplified side, elevation, bottom, and perspectiveexemplary views of embodiments of the key of FIG. 20.

FIG. 22 is an exemplary block diagram of an embodiment of the patientmonitor, sensor, and key of FIG. 20.

FIG. 23 is an exemplary block diagram of the key of FIG. 20.

FIG. 24 is a simplified flow chart of a measurement refill process,according to an embodiment of the key of FIG. 20.

FIG. 25 is a simplified flow chart of a communication process betweenthe key of FIG. 20 and a patient monitor, according to an embodiment ofthe disclosure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates a physiological measurement system 10 having amonitor 100 and a reusable multiple wavelength sensor 200 with enhancedmeasurement capabilities as compared with conventional pulse oximetry.In particular, the multiple wavelength sensor assembly 200 allows themeasurement of blood constituent and related parameters in addition tooxygen saturation and pulse rate. Alternatively, the multiple wavelengthsensor assembly 200 allows the measurement of oxygen saturation andpulse rate with increased accuracy or robustness as compared withconventional pulse oximetry.

In one embodiment, the sensor assembly 200 is configured to plug into amonitor sensor port 110. A monitor keyboard 160 provides control overoperating modes and alarms, to name a few. A display 170 providesreadouts of measured parameters, such as oxygen saturation and pulserate, along with sensor life information, to name a few. The keyboard160 can be pressed to change a display 170 readout from one parameter toanother, such as from percentage oxygen saturation to percentagecarboxyhemoglobin, and one parameter readout may be provided in adifferent color from another parameter readout. An artisan willrecognize from the disclosure herein that many types of monitors fallwithin the scope of this disclosure and that monitor 100 generally cancomprise electronic monitoring circuitry to determine or monitor patientinformation from appropriate sensors communicating with body systems ortissue.

FIG. 2 illustrates an embodiment of a disposable multiple wavelengthsensor 201 configured for finger placement. The sensor 201 has a tapeend 220 and an opposite connector end 210 electrically and mechanicallycoupled via an interconnect 240. The tape end 210 attaches an opticalassembly to a tissue site. An emitter transmits light into the tissuesite and the detector generates a sensor signal responsive to thetransmitted light after tissue absorption. The sensor signal iscommunicated via the interconnect 240 to the connector 250. Theconnector 250 mates with a patient cable (not shown) that communicatesthe sensor signal to a monitor 100 (FIG. 1). The monitor calculates avariety of physiological parameters from the detector signal, such aspulse rate (PR), oxygen saturation (SpO2), carboxyhemoglobin (HbCO),methemoglobin (HbMet) and total hemoglobin (Hbt), to name a few. Asensor configured for measurement of at least some of theabove-mentioned physiological parameters is described in U.S.Provisional Application Ser. No. 60/920,474, filed Mar. 27, 2007, titledDisposable Multiple Wavelength Optical Sensor, and U.S. ProvisionalApplication Ser. No. 60/923,630, filed Apr. 14, 2007, titled DisposableMultiple Wavelength Optical Sensor, both applications incorporated byreference herein.

FIG. 3 illustrates a physiological measurement system 300 incorporatinga medical device life monitor 339. A sensor 301 houses emitters 305responsive to drivers within a sensor controller 332 so as to radiatelight having a multiplicity of wavelengths. The sensor 301 also houses adetector 306 that provides a detector signal responsive to the emittedlight after absorption by pulsatile blood flow within a tissue site. Thedetector signal is filtered, amplified, sampled and digitized by themonitor front-end 336 and input to a DSP (digital signal processor) 338,which also commands the sensor controller 332. The cable 308electrically communicates drive signals from the monitor's sensorcontroller 332 to the sensor emitters 305 and a detector signal from thedetector 306 to the monitor front-end 336. The monitor connector 321plugs into the sensor port 320. Medical device life monitor 339 firmwareexecutes on the DSP 338 so that the processor board 330 may read andmodify usage information on sensor memory 307 or information element andor cable memory 322 or information element, as described in furtherdetail below.

In one embodiment, the monitor connector 321 houses the informationelement 322, such as memory or other active or passive electricalcomponent. In a particular embodiment, the information element 322 is anEPROM, or other programmable memory, or an EEPROM, or otherreprogrammable memory, or combinations thereof. In an alternativeembodiment, an information element 307 is housed within the sensor 301,or an information element is housed within both the monitor connector321 and the sensor 301. A reader/writer 334 inputs the informationelement 322 data to the DSP 338 for reference and modification by themedical device life monitor 339 according to sensor usage.

In one embodiment, the DSP 338, controller 332, front-end 336 andreader/writer 334 are a portion of a processor board 330 incorporatedinto the monitor 302. The processor board 330 communicates with amonitor CPU 350, which processes keyboard 360 inputs and providesdisplay 370 outputs, including physiological parameters and sensor lifeusage calculated by the DSP 338.

FIG. 4 illustrates physiological measurement system 400 embodimenthaving processor 410, sensor 420 and cable 430 components. In oneembodiment, the processor 410 has a processor printed circuit board“board” 412 and an optional daughter board 414, which plugs into andexpands the functionality of the processor board 412. For example, thedaughter board 414 may be a noninvasive blood pressure (NIBP) controllerthat communicates with a blood pressure sensor and the processor board412 so as to measure blood pressure parameters, or in other embodiments,may include an acoustic respiration controller or the like.

Also shown in FIG. 4, in one embodiment the sensor 420 is a “resposable”sensor comprising a reusable portion 422 and a disposable portion 424.In a particular embodiment, the reusable portion has at least one of areusable emitter portion and a reusable detector portion, and thedisposable portion 424 has at least one of a disposable emitter portion,a disposable detector portion and a disposable tape for attaching thereusable sensor 422 to a tissue site. A resposable sensor is describedin U.S. Pat. No. 6,725,075 entitled Resposable Pulse Oximetry Sensor,assigned to Masimo Corporation and incorporated by reference herein.

Further shown in FIG. 4, in one embodiment the cable 430 is a patientcable 432 or a sensor cable 434 or a combination of a patient cable 432and a sensor cable 434. A sensor cable 434 is fixedly attached at oneend to a sensor and has a connector at the other end for attaching to amonitor or a patient cable. A patient cable 434 has connectors at bothends for interconnecting a sensor or sensor cable to a monitor. In anadvantageous embodiment various ones of the processor 410, sensor 420and cable 430 have memories or information elements storing device lifedata that can be read and modified by a processor board DSP so as tomonitor and control usage and life of these respective physiologicalmeasurement system components.

FIG. 5 illustrates a configuration process 500 for a physiologicalmeasurement system executed by a DSP 338 (FIG. 3) with respect toinformation elements. After system power-up, any information elementsare polled 510 so they identify themselves. Information is thendownloaded from the responding information elements 520. In oneembodiment, download information can be some or all of Identification(ID), Life and Parameters, to name a few. ID identifies a component, thetype of component generally, such as a sensor or cable, or a particularpart number, model and serial number, to name a few. As another example,ID for a disposable sensor portion may be an attachment location on apatient and ID for a reusable sensor portion may be a patient type.Life, for example, may be a predetermined counter written into an EEPROMto indicate the number of uses or the length of use of a particularcomponent. Then, Life is counted down, say each time power is applied,until a zero value is reached, indicating component expiration.Parameters specifies the measurements the component is capable ofsupporting, which may include, for example, one or more of SpO₂, HbCO,MetHb, fractional SpO₂, Hbt, NIBP and blood glucose to name just a few.With respect to a sensor, Parameters depend on the number of emitters,emitter wavelength and emitter configuration, for example. For a cable,Parameters depend on the number of conductors and connector pinouts, forexample. Parameters may also simply reflect a license to use acomponent, such as disposable tape, with respect to a particular systemconfiguration.

As shown in FIG. 5, components are identified 530 from downloaded IDinformation. If any of the information elements provide Lifeinformation, a check is made to determine if the corresponding componentis expired 540. If so, an error message is displayed 580. The messagemay be a warning to replace the component or it may indicate that thesystem is nonfunctional.

FIG. 6 illustrates a spot check monitor credit process 600 where aquantum of currency 610 is defined, specifying a price per use or perunit time. A sensor life is defined according to the permitted number ofuses or amount of usage time 620 for a spot check monitor or continuousmonitor, respectively. The sensor is manufactured 630 accordingly, e.g.with the sensor life 620 information stored in a sensor memory orinformation element. The sensor is then shipped and delivered to an enduser. If calibration is successful 650, as the sensor is used 640,sensor life 660 is subtracted, either by decrementing the allottednumber of uses or by subtracting usage time. Remaining sensor life isshown on the corresponding monitor display 670. If calibration fails,usage is not debited and an error message is displayed 680.

In various embodiments, all spot check monitor information fits withinthe memory space of the supported EEPROM memory parts. The spot checkmonitor provides support to expire an accessory device when the designedservice length for the device has been reached. The spot check monitorcontain configurable spot check monitor functions that determine how thespot check monitor information collected will apply to the life of theaccessory device. The spot check monitor contains a configurable lifelimit. The spot check monitor configuration contains a configurablepercentage at which a near expiration exception can be set. Theinformation collected by the spot check monitor is configurable. A spotcheck monitor information update period specified in minutes can beconfigurable in the spot check monitor configuration. The spot checkmonitor may provide a configurable minimum connection time increment fora device to technology board connection event. The expiration of a spotcheck monitor device can be checked and reported when the followingevents occur in the system: The spot check monitor device is initiallyconnected to a processor board. The system is in an off-patientcondition and the configured grace period has elapsed in the system.

The spot check monitor grace period maybe be configurable in the spotcheck monitor. When the spot check monitor device does not configure agrace period the spot check monitor may default to a value of 5 minutes.The spot check monitor can report the life left and the life limit inminutes when requested by a host system. The spot check monitor cansupport a secondary expiration mode that uses device use counts or aspot check and hourly usage based on a specific parameter beingcalculated in the system.

In various embodiments, a spot check monitor collects and stores thenumber of times a spot check monitor device has been used for a spotcheck for the sensor spot check monitor device. The spot check monitormay support a configurable spot check window, defined in seconds orother units of currency, measure, time or use, where the device can beused to display multiple measurements of a parameter and only incrementa spot check count once. In an embodiment, the spot check windowconfiguration may have a range from 0 to 30 minutes. The spot checkmonitor may support a configurable charge per spot check, defined inpennies or other units of currency (U.S. or foreign or may calculateexchange by any of a wide variety of known methods), measure, time oruse, that is applied to the configured life limit of the spot checkmonitor device. In an embodiment, the charge per spot check may have arange from 1 to 65,536 ($655.36) pennies. The spot check monitor maycollect and store the hourly usage, in minutes, of a parameter. Thehourly usage of a parameter may be collected and stored separately fromthe life monitor run time. The charge per minute, defined in pennies,may be configurable in the life monitor configuration. The charge perminute may have a range from 1 to 65,536 ($655.36) pennies.

In various embodiments, the spot check monitor parameters are one ormore of noninvasive SpHb, SpMet, SpO2, SpCO, although many otherparameters may advantageously be included. For example, other bloodconstituents, parameters or analytes, may include a percent value forarterial carbon monoxide saturation (“HbCO”), a percent value formethemoglobin saturation (a brownish-red form of hemoglobin that cannotfunction as an oxygen carrier) (“HbMet”), total hemoglobin (“HbT”),fractional SpO₂ (“SpaO₂”) or the like. Additionally, caregivers oftendesire knowledge of HbO₂, Hb, blood glucose (“HbGu”), water, thepresence or absence of therapeutic drugs (aspirin, Dapson, nitrates, orthe like) or abusive/recreational drugs (methamphetamine, alcohol,steroids, or the like), concentrations of carbon dioxide (“CO₂”), oxygen(“O₂”), pH levels, bilirubin, perfusion quality, albumin,cyanmethemoglobin, oxygen content (“CaO2”), and sulfhemoglobin(“HbSulf”), signal quality, respiration, sedation, combinations of thesame or the like. Accordingly, the present disclosure includes amulti-parameter patient monitor capable of determining one or more ofthe foregoing parameters, other than or in addition to, SpO₂,plethysmograph waveforms, perfusion quality index, or pulse rate.

In an embodiment, the sensor will not expire during active patientmonitoring. During a sensor off condition while the sensor is expired, acertain amount of time may be given to the user to re-apply the sensor.Once measurements have reached the display “Ready” state on the device,a sensor time of 10 minutes or 1 spot check use may be decremented.Sensor may have a defined number of hours of active SpHb monitoring anduses for Spot Checks. Additional checks can be performed within apredetermined number of seconds (˜20 sec) from the initial use with noimpact to the sensor use time or count. The error message display whenSensor Life Expires may be “Expired Sensor”. The display may show sensortime for 120 seconds when sensor is connected to device, applied to apatient or removed from a patient. Spot Check device may utilize asensor use bar graph. The display may show sensor time with an audiblebeep when remaining time reaches 4 hr, 2 hr, 1 hr, and 0 min.

FIG. 7 illustrates a spot check instrument 100 embodiment including ahandheld monitor 800 and a noninvasive, reusable finger-clip sensor 10for spot checking of pulse oximetry parameters, such as arterial oxygensaturation (SpO₂), pulse rate (PR) and perfusion index (PI) in additionto advanced blood parameter measurements, such as total hemoglobinconcentration (SpHb). The spot check instrument 100 is designed for usein hospitals, hospital-type facilities, homes, clinics, physicianoffices, blood donation facilities and ambulatory surgery centers, toname a few. The spot check instrument 700 advantageously works inconjunction with a spot check credit system that provides online accessfor purchasing, downloading and renewing sensor credits, with or withoutintervention of the manufacturer. Sensor credits pay for sensor usage ona spot check basis, where one credit enables a sensor to make a singlemeasurement of a group of predefined parameters, such as those listedabove. A blood parameter instrument including a monitor and noninvasivesensor is described with respect to U.S. patent application Ser. No.12/534,812 titled Multi-Stream Sensor Front Ends For NoninvasiveMeasurement of Blood Constituents; filed Aug. 3, 2009, assigned toMasimo Laboratories, Inc.; Irvine, Calif. and incorporated by referenceherein. A spot check monitor 800 is described in detail with respect toFIGS. 8A-C, below. A spot check measurement process is described indetail with respect to FIGS. 9A-D below. A spot check credit system isdescribed in detail with respect to FIGS. 10-19, below.

FIGS. 8A-C illustrates the spot check monitor 800 having a power button810, an LCD touchscreen 820, a sensor connector port 830, an earphonejack 840, a MicroSD card slot 850, a mini USB port 860 and a power port870. The power button 810 is pressed to turn the monitor 800 on or off.The touchscreen 820 is interactive, allowing a user to move throughscreens, select options, enter information and view instrument specificmessages. The sensor connector port 830 connects a reusable sensor 10 tothe monitor so as to enable spot check measurements of SpO₂, PR, PI andSpHb. The earphone jack 840 allows a user to listen to a parameter ormeasurement result using an earphone with a standard 3.5 mm plug. TheMicroSD card slot 850 accepts a flashcard to upload new software to themonitor 800 or additional spot check credits to an attached sensor 10(FIG. 7). The mini USB port 860 connects a mini USB-to-USB cable to theUSB port on a computer. This allows the computer to download newsoftware or additional spot check credits to the monitor 800 or uploadinformation, such as measurement results, to the computer. The powerport 870 connects to an AC/DC converter so as to provide DC power to themonitor 800 and/or charge monitor batteries.

As shown in FIG. 8A, the touchscreen 820 displays the number of spotchecks remaining in the attached sensor 821, the time of day 822 andbattery status 823, although an artisan will recognize from thedisclosure herein many other ways of interacting with the user toindicate the remaining spot checks, including for example,red-yellow-green indicators, separate audio or visual indicators, gasbars, pie charts, graphs, sounds, colors, fillable or drainable icons,combinations of the same or the like. The touchscreen 820 also displaysmeasured parameter values 824, such as total hemoglobin, oxygensaturation, pulse rate and perfusion index, as shown. The touchscreen820 also has “soft key” buttons 825 that have various functionsaccording to displayed icons. These functions may include “start atest,” “go to the main menu screen,” “submit inputs,” “move back ascreen,” “exit a screen,” “scroll up/down a list or page,” “display aninteractive dialogue for user options” or “add patient specificinformation,” to name a few.

To determine if a reusable sensor 10 (FIG. 7) contains spot checkcredits, it is connected to the monitor 800. A numeric value will appearin the top left corner of the screen 821, with the number of availablespot check credits it contains (e.g. 20). If one or more credits remain,“Ready” is displayed on the screen 820. If no spot checks remain, thescreen 820 will show 0 credits in the upper left corner 821 in red andthe message “No Spot Check Credits.”

FIGS. 9A-D illustrates the steps for making a measurement with the spotcheck instrument 700 (FIG. 7). The spot check sensor 10 (FIG. 7) isattached to the monitor's sensor port 830 (FIG. 8A). The power button810 (FIG. 8A) is pressed. The monitor 800 (FIG. 8A) generates an audibletone and displays a logo screen (not shown). If a sensor is not attachedor not connected completely, the monitor displays a “connect sensor”screen 910. Once a sensor is correctly connected, the monitor displays“ready” screen 920, indicating that a spot check test may proceed.Touching the display screen 820 (FIG. 8A) initiates the test. Themonitor displays a “testing” screen 930 while the test is running, whichincludes a timer that counts down the seconds until the test iscomplete. If motion is detected during testing, a motion bar at thebottom of the screen will begin to fill. If the entire bar is full, thetest will fail as a result of too much motion. After a successful spotcheck test, the monitor generates an audible tone and displays a resultscreen 940 showing various parameter values. Further, after the testdetailed information about a patient can be entered by touching theappropriate soft key. If printer or email options are set up, a printerand/or email soft key will appear at the bottom of the screen allowingthe test results to be sent to a designated printer or email addressaccording to on-screen instructions.

FIG. 10 illustrates a spot check credit system 1000 having a server1005, web pages 1400, an account management application 1100, a creditfile application 1202 that generates credit files 1201, a sensor IDvalidation script 1037 and an application database 1032 that includesinformation regarding user accounts 1034 and registered equipment 1035.The spot check credit system 1000 communicates with multiple “clients”1020 via the Internet 1002. Clients 1020 may be any of various devicessuch as PCs, laptops, smart phones and various e-readers/pads to name afew. Clients 1020 access the Internet via cable, DSL or fiber-optics orvia wireless technology including Wi-Fi, EV-DO, HSPA, WiMax, LTE orother cellular and satellite technologies to name a few. Clients 1020may be in communications with spot check instruments 700 including spotcheck monitors 800 and corresponding sensors 10, such as described withrespect to FIGS. 7-9, above. One advantageous aspect of the spot checkcredit system 1000 is interactive online instrument management, salesand support related to spot check blood parameter measurements. Variousfunctions of a spot check credit system 1000 include spot check creditpurchase and download; spot check test data and device status upload,such as raw data, use statistics and trends; software updates; purchaseof equipment and accessories, including discounts and specials; salesand account management; training and technical support, including livehelp, videos, manuals and documents; related health management news; andfeedback, including testimonials, surveys and issues; to name a few.

In an upload embodiment, a user option offers a choice of emailing spotcheck test results to engineering support for the analysis of successfuland unsuccessful tests. In another upload embodiment, when a monitor 800is connected to a client 1020, the monitor 800 uploads a copy of allspot check test results. Corresponding monitor status, if any, is alsouploaded. The test results advantageously have all patient identifyingdata removed, or include a wide variety of mechanisms for dealing withpatient data which may be confidential or otherwise regulated by thecaregiver, business concern, the government, or combinations of thesame. The client 1020 then uploads the test results to the server 1005for manufacturer analysis. In yet another upload embodiment, when amonitor 800 wirelessly connects 1004 directly to the server 1005, testresults and any corresponding monitor data is uploaded to the server1005 prior to, concurrently with or subsequent to transferring credits,software updates or other downloads to the monitor. Uploaded monitordata may include raw sensor data, processed waveform data, usestatistics, such as how many tests are administered, test time of dayand the number and time of monitor power-ups, to name a few. A spotcheck credit system advantageously allows teams from engineering,clinical research or marketing to collaborate online to process andreview collected uploads to determine trends, statistics and variablesin patient demographics, instrument use, signal processing algorithmbehavior and raw sensor data for use in engineering development, clientmanagement and patient management, as examples.

As shown in FIG. 10, the server 1005 provides web pages 1400 to theclients 1020 at a predetermined web site address (generically denoted“xyz.com” herein). The account management application 1100 determinesthe website functionality in response to client inputs. The credit fileapp 1202 generates a credit file 1201, which includes a sensor IDverified by the validation script 1037. The user accounts 1034 anddetails of registered equipment 1035, including monitors and sensors,are stored on the database 1032 among other data.

Also shown in FIG. 10, a particular advantageous aspect of the spotcheck credit system 1000 is a website for the purchase and onlinedelivery of sensor credits. A purchased credit file 1201 containing aspecified number of credits is downloaded to a client device 1020, andthen to a spot check monitor 800, which loads the credits into thesensor 10. Measurement results may be uploaded as reports to the client1020 and advantageously delivered to an arbitrary email address via theserver 1005. In another embodiment, credits are wirelessly downloaded1004 directly from the server 1005 to a spot check monitor 800 andreports are wirelessly uploaded directly from the monitor 800 to theserver 1005, bypassing the client computer or device. Account management1100 is described in further detail with respect to FIG. 11, below.Credit files 1201 and credit file downloads are described in furtherdetail with respect to FIGS. 12A-B, below. Web pages 1400 are describedin further detail with respect to FIGS. 14-19, below.

Although a server 1005 is described above as a unified device at aspecific location, in other embodiments the server 1005 comprises a webserver 1010 distinct from the database server 1030. In an advantageousembodiment, the web server 1010 is located at any of various commercialserver “farms.” The database server 1030, however, is located at aprivate, secure location, such as corporate headquarters so as to moreeasily protect sensitive customer, sales and patient information. Insuch an embodiment, the database server 1030 communicates with the webserver 1010 over a leased line, a virtual private network or othersecure communications link.

FIG. 11 illustrates a spot check credit process 1100 showing interactionbetween a user 1101, a monitor 1103 and the spot check web server 1105or sales staff in terms of basic functions 1107 and enhanced functions1109. A user may request a device 1110, including a monitor 800 (FIG. 7)or sensor 10 (FIG. 7), via sales 1112 or via a spot check credit website1116. A web account is created 1120 accordingly, either by the salesstaff 1112 or directly from the website 1116, providing the user with aname and password 1117 so as to access the account.

As shown in FIG. 11, a web account advantageously enables email 1130 onthe monitor. This allows the user to upload user information and devicereports 1132 to any user computing device, such as a PC, smart cellphone, PDA or electronic pad. In an embodiment, the user provides anyemail address, which is stored on the server 1105 (FIG. 11). In variousembodiment and for security concerns, email can be routed to the server,which then relays it to the user-provided address.

Also shown in FIG. 11, a particularly advantageous function of the spotcheck credit process 1100 is to facilitate the purchase and delivery ofspot check credits to a sensor. A web account 1120 allows the user topurchase spot check credits for a sensor online. A user requests spotcheck credits 1140 for a sensor in several ways. The user can login tothe spot check web site 1144 from any computer with Internet access, asdescribed with respect to FIG. 10, above. The credits are purchased bycredit card, invoice or other well-known payment methods. The serverresponds by downloading a credit file, as described with respect toFIGS. 12A-B, below. The credit file is transferred to the monitordirectly via USB cable 1148 or indirectly by writing the credit fileonto a MicroSD card 1146. Once loaded, the MicroSD card is removed fromthe computer and inserted into the monitor. Downloading a credit filefrom the monitor to the sensor is described further with respect toFIGS. 13A-B, below. In another embodiment, a monitor downloads a creditfile wirelessly using, for example, a Bluetooth connection to the usercomputer or a Wi-Fi connection direct to the Internet, without the needfor a separate computer, as described with respect to FIG. 10, above.

Further shown in FIG. 11, the user can telephone or otherwise contactsales support. Sales staff can then login to the spot check web site1142 to purchase credits for the user, download the credit file to aMicroSD card, and ship the card to the user accordingly. A user can alsoemail sales via the monitor 1160 (and attached computer) so as topurchase credits via shipped MicroSD card. Besides sensor credits, theuser 1160 can login to the spot check website 1150 so as to customizemonitor features including the addition of parameters or thecustomization of screen and sound interfaces, to name a few.

FIG. 12A illustrates a credit file 1201 having a time stamp 1212, asensor ID 1214 and credits 1215. The time stamp 1212 is an integrityfeature of the credit file 1201. The sensor stores the time stamp of thelast credit file downloaded. A monitor reads the sensor time stamp toverify it is older than the time stamp of the credit file to download.If the sensor time stamp is newer than (or the same as) the credit filetime stamp, then the credit file is not downloaded. In this manner,reuse of credits is prevented. In an embodiment, the time stamp 1212 isa universal time code (UTC). In other embodiments, any sequential numberscheme can be used in lieu of a time stamp so as to distinguish new andused credit files. In alternative embodiments, verification of a creditfile time stamp is done in the sensor or both the sensor and themonitor.

Also shown in FIG. 12A, the sensor ID 1214 is another integrity featureof the credit file 1210. In an embodiment, the sensor ID 1214 is aunique 16 digit (hexadecimal) number assigned to and stored within eachspot check sensor 10. A monitor reads the sensor ID to verify it isidentical to the credit file sensor ID. If not, the credit file is notdownloaded. In this manner, credits purchased by a particular customerfor a particular sensor cannot be used by another customer or foranother sensor. Advantageously, the time stamp and sensor ID integrityfeatures dissuade the use of counterfeit, knockoff or grey marketsensors and facilitate data collection and research, as described withrespect to FIG. 4, above.

Further shown in FIG. 12A, the credit file 1201 has a specified numberof spot check credits 1215, which can be added to existing sensorcredits, if any, so as to replenish sensor usage. In addition, theentire credit file 1201 including the time stamp, ID and credits isencrypted 1217 to further ensure file integrity.

FIG. 12B illustrates a credit file downloading process 1200, whichresults in credits added to a sensor 10. The process is initiated by acredit request 1220 that is initiated in the web server 1010 (FIG. 10)and relayed to the database server 1030 (FIG. 10) in response to a useror sales request, as described with respect to FIG. 11, above. Thedatabase server 1030 (FIG. 10) initiates a spot check credit application1202 in response, which assembles the credit (binary) file 1201 (FIG.12A). In particular, a sensor ID validation script 1037 (FIG. 10)verifies the sensor ID 1222 associated with the request. This insuresthat the addition of sensor credits does not fail when the monitor 800eventually compares the sensor ID with the ID read from the sensor 10.

As shown in FIG. 12B, the credit file 1201 (FIG. 12A) is then assembled1224 by generating the time stamp and credits and appending the sensorID. A script then encrypts the credit file 1226. The web server 1010(FIG. 10) and intervening computer 1020 (FIG. 10) then transmit 1230 thesensor file to the monitor 800, as described with respect to FIG. 10,above. The monitor 800 decrypts the credit file 1232, reads the sensor1234 and verifies the sensor ID and time stamp 1236, as described withrespect to FIG. 12A, above. Once the credit file is verified, thecredits are added 1242 to the sensor 10 in the amount of the credit filecredits 1215 (FIG. 12A).

FIGS. 13A-B illustrates the downloading of credits via USB cable. Newsensors 10 (FIG. 7) typically come with a certain number of creditspreinstalled. Each sensor has a serial number that can be found byconnecting the sensor to the monitor 800 (FIG. 7) and then selectingMenu>Help>Equipment Report. Once credits are ordered, a digital file isdownloaded to a user computer, sent via email or physically mailed on aMicroSD card. Credits are installed onto the sensor via the monitor, asdescribed above, using a MicroSD card or using a USB cable. Using aMicroSD card, the sensor is connected to the monitor, the MicroSD cardwith spot check credits on it is inserted into the MicroSD card slot,and the MicroSD load button is pressed. A dialog will appear confirmingthe credits have been successfully loaded.

As shown in FIG. 13A, when a USB cable is connected between a computerand the monitor, the monitor indicates “USB connected.” On the computerside, the monitor appears as a mass storage device, e.g. like a USB jumpdrive. The purchased credit file is then dragged into the monitor“drive.” The monitor then indicates “Files transferring.” Once the filehas completed downloading to the monitor drive, the standard computerprocedure for ejecting an external mass storage device is used to“eject” the monitor. The USB cable is then disconnected from the monitorand computer.

As shown in FIG. 13B, after the credit file download, the monitor showsthe credit file data including the number of credits, the sensor ID andthe time stamp (UTC). The monitor also shows the sensor data includingcredits remaining the sensor ID. The load button is pressed and a dialogappears confirming the credits have been successfully loaded. Ifmultiple Spot Check credit files have been purchased, the credit filesmust be loaded in sequential order (i.e. credit file purchased Apr. 3,2010 prior to credit file purchased Apr. 15, 2010. Non-sequentialloading of credit files will obsolete any skipped credit files. Ifcredit files are available in different locations (one on the MicroSDand one on the Internal Device Storage) the monitor only allows loadingof the oldest file first. After the oldest file is loaded, then the nextmost recent credit file can be loaded.

FIG. 14 provides an overview of a spot check credit website having a URLgenerically described as xyz.com. When a user enters the URL in abrowser, the website responds with a login page 1401 requesting a username and password. When entered, the server recognizes the login asbelonging to a sales manager, a sales representative (rep), a customeror a website administrator. If a sales manager logs in, they aredirected to a manager's welcome page 1410, as shown in FIG. 15A. If asales representative logs in, they are directed to a rep's welcome page1420, as shown in FIG. 15B. If a customer logs in, they are directed toa customer's welcome page 1430, as shown in FIG. 15C. If a siteadministrator logs in, they are directed to an administrators welcomepage 1440, as shown in FIG. 15D.

As shown in FIG. 15A, the sales manager's welcome page 1410 has tabs fornew reps (default page), my sales reps (FIG. 16A) and notify reps (FIG.16B). As shown in FIG. 15B, the sales rep's welcome page 1420 has tabsfor new customers (default page), my customers (FIG. 17A), issue credits(FIG. 17B) and notify customers (FIG. 17C). Equipment (FIG. 18A) andcredit download (FIG. 18B) pages can be accessed via my customers (FIG.17A) and issue credits (FIG. 17B) pages, respectively. As shown in FIG.15C, the customer's welcome page 1430 has tabs for equipment (defaultpage), credits (FIG. 19A), request equipment (FIG. 19B), softwareupdates (FIG. 19C) and tech support (FIG. 19D). As shown in FIG. 15D,the administration welcome page 1440 provides a summary of all users,equipment, software updates and credits issued. Additional tabs providefor modifying credit generation script or for uploading softwareupdates, as examples.

In various additional, optional, or combination embodiments, thedisclosure herein includes a patient monitor capable of electronicallytracking patient measurements on a per-use basis. Moreover, embodimentsof the disclosure include a device for communicating with the patientmonitor to provide authorization and accounting for measurements, forexample, a device that refills or increases the available number of usesleft on the patient monitor. In an embodiment, the device includes aphotocommunicative key for communicating payment, credit, or otherinformation to the patient monitor to facilitate billing on, forexample, a per-use basis. Additionally, the key may advantageously storeinformation, some of which may be sensitive. In an embodiment, the keymay include measurement information useful to a manufacturer to manageand improve monitor performance. The key may include measurementinformation useful to a caregiver, or information useful to a patientbeing monitored, combinations of the same or the like. This informationmay include past measurements, trending information, timing ofmeasurements, other parameter information during measurements includingvital signs, etc., demographic data, personal medical histories,combinations of the same or the like.

In some embodiments, the photocommunicative key communicates with one ormore monitors configured to at least measure a blood analyte throughanalysis of signals indicative of an absorption of light by tissue.Thus, the monitor is often associated with and designed to providecommunication to and from one or more noninvasive sensors, eachincluding a light source or emitter(s) and light detector. The detectoris configured to output a signal indicative of light from the lightsource after attenuation by body tissue. In an embodiment, the key ofthe present disclosure advantageously communicates with the monitorthrough the electronics of the noninvasive sensor.

For example, in an embodiment, the key may be configured to communicatethrough associated pairs of emitters and detectors. For example, the keyitself may include one or more detectors capable of outputting a signalresponsive to detected light from, for example, the light source(s) ofthe noninvasive sensor of the monitor. The signals may advantageously bepreprocessed and/or forwarded to a key processor or controllerconfigured to determine the information encoded in the detected light.The key processor may also output signals to one or more key lightsources or emitters that encode information in a signal of emitted lightto be detected by the detector of the noninvasive sensor of the monitor.Through these receiving, decoding, encoding and emitting protocols, thekey may advantageously communicate with a patient monitor through, forexample, an associated sensor.

Through the foregoing communication, the key may obtain usageinformation for one or more monitors, manage debits and credits from acredit supply, may obtain software upgrades, firmware for the key and/orthe monitor, monitor statistics, monitor and/or supply identifyinginformation, encryption keys, sensor use and/or sensor information,stored monitoring data, combinations of the same or the like. The keymay also forward information to one or more patient monitors, theinformation including some or all of the information received.

In some embodiments, a key encoder may advantageously provide the keywith forwardable measurement credits, which the key in turn provides tomonitors with whom it communicates. The key encoder may comprise asimilar light exchange described above with a sensor or other devicespecifically designed to communicate with the key, may communicatewirelessly with any multitude of digital processing devices includingPCs, phones, servers, and other computing devices, or the like.

In some embodiments, the emitters on the patient monitoring device maybe used to provide some or all of the desired power to thephotocommunicative key.

For purposes of summarizing the invention, certain aspects, advantagesand novel features of the invention have been described herein. Ofcourse, it is to be understood that not necessarily all such aspects,advantages or features will be embodied in any particular embodiment ofthe invention.

In an embodiment, the present disclosure includes a key or a processingdevice designed to communicate with a patient monitor. While thecommunication may include any useful communication between (a) monitorsin the field and (b) keys that may be at times communicate with thatmonitor's manufacturing company, the photocommunicative key of thepresent disclosure also includes the software and/or hardware providingcommunication that tracks and accounts for patient use of one or moremonitoring devices. For example, in a straightforward implementation, apatient monitor may advantageously track its use through one or morevalues or formulas. For example, in an embodiment where the monitorprovides spot check patient monitoring, such as, for example, totalhemoglobin, glucose, ph, oxygen content, other blood analyte,respiration, combination of the same or the like, the monitor may trackthe number of times it has been used to provide spot check measurements.The monitor may also associate measurements with patient information orcodes usable to associate particular measurements, or counts ofmeasurements with a payor of a measured patient's or group of patients'medical care.

It will be appreciated from the disclosure herein that a measurement asdisclosed above may have a number of definitions, some preferablyassociated with a particular monitor's use characteristics or aparticular type of billing. For example, in the spot check device of theforegoing, the spot check device may make many actual calculations andtake many measurements of one or many physiological parameters, groupsor combinations of physiological parameters or the like to determine asingle output to the spot check display. In such a device, an embodimentof the disclosure may advantageously use the act of providing a singleoutput to the spot check display as a billable measurement.Alternatively, a user or caregiver input or inputs may identify anactivity that qualifies or does not qualify as a billable measurement.For example, a user or caregiver or service representative may deleteotherwise billable measurements determined to have been performedunsatisfactorily, in error, as a test or demonstration, as training, ascomplementary or the like. The billable measurement may be userconfigurable to adjust to the particular monitoring requirements of agiven monitoring situation. In an embodiment, a formula or formulas maybe implemented to track what constitutes billable activity on theinstrument. For example, a number of electronic events may be includedas part of a count or timer where a predetermined total or elapsed timecreates a billable event, or the like. In an embodiment, some or all ofthe formulas may be uploaded from the disclosed key providing adjustableor customizable billing.

In some embodiments, the key may advantageously be a way of trackingmultiple billing events and/or entities in a caregiver or otherenvironment. For example, a key may advantageously be provided to eachpatient at a hospital, caregiver facility or the like. The key mayadvantageously store all kinds of medically relevant and demographicinformation about the patient, including for example, recent measurementdata from a wide variety of medical monitoring or measurement equipment,caregiver comments, observations, diagnosis, portions or entire medicalhistories, or the like. An artisan will recognize from the disclosureherein that storage of such data on individual portable memories, suchas the foregoing key, reduces the likelihood of privacy violations oftenfound in large monolithic hospital systems.

An artisan will recognize from the disclosure herein a large variety ofdifferent accounting methodologies that may be implemented within themonitor to assign billable events to that monitor's activities. Forexample, in continuous monitoring situations, timers or other usetracking methodologies may be more advantageous that the morestraightforward spot check monitor.

In an embodiment the key or digital device may advantageouslycommunicate with the monitor through an attached or communicatingsensor. For example, the key may use existing communication protocolsbetween sensors and the monitor to communicate monitor measurement ormonitor use information, patient related information, software upgrades,combinations of the same or the like. Such information may include theforegoing accounting type information, may include information useful tothe manufacturer to manage monitor behavior and functionality, mayinclude information useful to the patient or caregiver, such asmeasurement, demographic, patient use or other information, and mayinclude billing information or the like.

To facilitate a complete understanding of the invention, the remainderof the detailed description references the figures. For example, FIG. 20illustrates an exemplary perspective view of an embodiment of a patientmonitoring system 2000 including a patient monitor 2002, a sensor 2004,a cable 2006 providing communication between the monitor 2002 and thesensor 2004, and a photocommunicative key 2008 providing communicationbetween the monitor 2002 and the key 2008 through the sensor 2004 andattaching cable 2006. In an embodiment, the patient monitor 2002comprises a monitoring device configured to process signals indicativeof one or more physiological parameters of a patient and determinemeasurement values for the some, all, or combinations of the parameters.The monitor 2002 outputs those values to the display 2010 or any otherconnectivity capability built into the monitor 2002 for caregiverreview. The monitor 2002 may also include user interaction through userinterface devices 2012, which in an embodiment may include controlbuttons, touchscreens, voice interaction, pointer input, or other commonuser interface technologies.

Monitors according to the present disclosure can include aspects ofthose monitors commercially available from Masimo Corporation, MasimoLabs, Inc., or Cercacor Inc., each of Irvine, Calif. In addition, themonitors may comprise monitors disclosed in U.S. Pat. Nos. 6,157,850,6,584,336, 7,530,949, and U.S. Pat. App. Pub. No. 2010/0030040, owned byMasimo or Cercacor, the content of which at least relating to monitortechnologies is incorporated by reference herein.

In an embodiment, the monitor 2002 comprises a spot check monitor forone or more of total hemoglobin, pulse rate, oxygen saturation, carbonmonoxide saturation, methemoglobin, brain oxygenation, depth ofsedation, glucose, ph, perfusion indications, signal qualityindications, combinations of the same or the like. An artisan willrecognize from the disclosure herein that other monitors monitoringadditional or other parameters may benefit from the accountingdisclosure below, and the present disclosure is not limited to the typesof specific monitors referenced above.

FIG. 20 also illustrates the sensor 104 comprising a noninvasivereusable sensor including light sources and detectors configured todetect light attenuated by tissue at the measurement site, in this case,at a digit of the patient. Sensors according to the present disclosurecan include aspects of those sensors commercially available from MasimoCorporation or Cercacor Corporation, may be disposable, reusable,wireless or combinations of the same. In addition, the sensor maycomprise sensors disclosed in U.S. Pat. Nos. 6,088,607, 6,011,986, andU.S. Pat. App. Pub. No. 2010/0030040, owned by Masimo or Cercacor, thecontent of which at least relating to sensor technologies isincorporated by reference herein.

As is understood in the art and disclosed generally with reference toFIG. 22, the monitor 2002 outputs a drive signal through the cable 2006to drivers of the light source(s) or emitter of the sensor 2004, causingthe light source(s) to emit light. Detectors positioned to receive theemitted light after attenuation by body tissue detect the light andoutput a signal indicative of the various physiological parameters ofthe body tissue from the wearer of the sensor 2004. The signal ispreprocessed by front end hardware and or software electronics and thenforwarded to one or more controllers and/or processors to electronicallyprocess the signal and to determine output values for display andeventually caregiver review. In an embodiment, the monitor 2002 includesthe display 2010 and the user interface 2012. As shown in FIG. 22, theprocessor may communicate with memories associated with the sensor,scratchpad memories, software storage, program storage, and the like. Inaddition, the monitor 2002 may communicate with network interfaces toprovide communicate to and from the signal processor.

Returning to FIG. 20, FIG. 20 also shows an embodiment where the key2008 is shaped to at least roughly mate with mechanical aspects of thesensor 2004 in the sense that coupling of the roughly mateble portionsposition the key 2008 in a way to ensure optical and/or electroniccommunication between the key 2008 and the sensor 2004. For example, thekey 2008 may include mechanical indentations configured to at leastpartially match protrusions of the sensor 2004. In an embodiment, thekey includes one or more light sources, one or more detectors, andoptionally a grip portion and/or a lanyard.

In an embodiment, the monitor 2002 tracks use or is configured to makemeasurements when there are sufficient measurement credits available.For safety, a certain number of emergency measurements may beimplemented to allow measurements without credits. Such measurements maybe billed at a later time, possibly with a differing rate, or otherwisebe outside the normal spot check per measurement billing methodology.However, in the normal course, when the hand-held monitor 2002 is used,the number of credits available may be decremented. Once there are nocredits left, the hand-held device may generally disable itself untilmore credits are made available. One manner of providing more credits tothe hand-held device may be to connect the hand-held device directly toa digital device, possibly via the internet, that can load more creditsonto the device. Wireless or other traditional digital devicecommunication, such as through a portable memory, could also beemployed. In an embodiment, the key 2008 may include commonly understoodcommunication mechanisms, such as, for example, USB, Bluetooth, or otherwireless protocols. As shown, the key 2008 includes opticalcommunication functionality and USB functionality such that the key 2008may communicate with an instrument or a refill module through opticalinteractions described further below, and/or through USB communicationwith PCs, mobile phones, PDAs or other computing devices.

Another manner of getting more credits onto the hand-held device may beto provide the photocommunicative key 2008 that has stored on it creditsto be communicated to the monitor 2002. The key 2008 may also be used toprovide software or firmware upgrades to the monitor 2002. The key 2008may communicate with the patient monitor 2002 using a number ofdifferent communication components. For example, the patient monitor2002 may communicate with the key 2008 using photodetectors andphotoemitters associated respectively with opposing photoemitters andphotodetectors, respectively, of the key 2008. There are severalvarieties of photosensors and opposing, complementary, matched, or thelike, photoemitters that may used for this communication. For example,the photodetectors and photoemitters may advantageously include opticaldetectors, chemical detectors, such as photographic plates,photoresistors or light dependent resistors (LDR) which may changeresistance according to light intensity, photovoltaic cells or solarcells which produce a voltage and supply an electric current whenilluminated, photodiodes which may operate in either a photovoltaic modeor a photoconductive mode, photomultiplier tubes, which may contain aphotocathode which may emit electrons when illuminated, phototubes,which may contain a photocathode that emits electrons when illuminated,phototransistors, pyroelectric detectors, Golay cells, thermocouples andthermistors, cryogenic detectors, charge-coupled devices (CCD), and/orLEDs reverse-biased to act as photodiodes. The emitters or light sourcesmay be LEDs, halogens, tungsten-based, xenon-based, deuterium-based, orany other type of light source. The words “emitter” and “detector” asused herein may correspond to any or multiple of the types ofphotodetectors or photoemitters, or groups of detectors or emitters,disclosed, referenced, or implied herein or in the art.

As shown in FIGS. 21A-21D, the photocommunicative key 2008 may at leastin part be roughly be shaped like a finger, or substantiallycylindrical, to allow it to at least partially mechanical mate with thestructure of a given sensor 2004 such that the optical elements arecorrectly and straightforwardly aligned when the key 2008 is insertedinto the sensor 2004. As shown in FIGS. 20-21, in an exemplaryembodiment, the sensor 2004 may include a raised ridge within thefingerbed to, for example, create a more consistent and predictablefinger shape when the sensor 2004 is taking measurements. As shown inFIG. 21C, the shape of the raised ridge may be advantageously hollowedout of the shape of the key 2008 to ensure proper vertical andhorizontal alignment when the key is inserted into the sensor 2004.Additionally, transparent windows may advantageously cover and protectat least the emitter and detector light paths of the key 2008 allowinglight to pass through portions thereof. In an embodiment, the internalsof the key 2008 may be advantageously formed, coated, or otherwiseconfigured to reduce light received from the emitters of the sensor 2004from bleeding or piping through the key 2008 to the detectors of thesensor 2004.

FIG. 21 also shows that the key may include a grip portion forstraightforward handling. An artisan will recognize from the disclosureherein that the shape of the key 2008 can take many forms.Considerations in shaping the key may include mechanical stops or gapsthat mate or substantially mate with the sensor 2004 or other matingdevice to properly position the key for communication, such as, forexample, optical communication through transparent windows. The key 2008may be shaped to reduce light piping or interference from exterior lightor noise sources. The key 2008 may be shaped, colored, and/or branded touniquely identify its manufacturer, controller, service provider or thelike. If the patient monitor 2002 or sensor 2004 is configured or shapedto monitor another body part, such as an ear lobe, then thephotocommunicative key may be shaped to match that body part. If thepatient monitor 2002 has particularly-shaped padding, the key 2008 maybe shaped to fit well in only one manner with the padding on the patientmonitor 2002. In an embodiment, the key 2008 may use any appropriatevoltage and amperage, corresponding to any communication or otherscheme, protocol, or the like, such as, for example, approximately 5volts at approximately 30 milliamperes; however many other combinationsare within the scope of the disclosure.

In an embodiment, a digital processor may program the key 2008 to, forexample, communicate payment or credit information. In an embodiment, aprocessor communicates with a communication module that mayadvantageously include lights sources and detectors similar to thatdescribed below with reference to key-sensor communication. That is, anemitter may emit radiation detectable by the key detector and the signalmay be translated into an electronic signal and sent to the keyprocessor to update, for example, measurement credits available on thekey 2008 or subscription information or, in some embodiments, upgrade tosoftware or firmware.

In some embodiments, the instrument may receive credit information orsubscription information via the Internet or a direct connection betweenthe instrument and a device capable of providing credit information orsubscription information, such as a personal computer, cell phone, orthe like.

In some embodiments, some or all of the communication disclosure hereinmay be encrypted. Those of ordinary skill in the art will be familiarwith the encryption techniques useful for encrypting the stored data andcommunications, including public/private key encryption, password-basedencryption, secret-key-based encryption, or the like. Encryption may beused to make copying or duplicating the information on thephotocommunicative key 2008 or the patient monitor 2002 difficult.Encryption may also alleviate some potential privacy concerns with thestorage and transmittal of usage information.

FIG. 22 illustrates an exemplary block diagram of the key 2008 incommunication with a patient monitor 2002 through the sensor 2004. Insome embodiments, the key 2008 may include one or more detectors, one ormore emitters, one or more memories, or the like each communicating withone or more microprocessors or controllers. In addition, the key 2008may include preprocessing modules for noise reduction. As will beunderstood from the disclosure herein, electronic components of the key2008 may communicate with one another along conductive paths as part ofa printed circuit board, as separate components, across wires, or thelike. For example, the microprocessor may be coupled to detectors aswell as to memory and the emitters. As is discussed in more detailherein, the key memory may store information relating to credits,subscriptions, patient information, measurement or operationalinformation, and/or software or firmware upgrades for patient monitor2002.

The key microprocessor may be used to generate a signal to be sent outby the emitter based on information stored in the key memory. Forexample, if the key memory is storing information relating to additionalcredits, then the key microprocessor may generate a signal to be emittedby emitter and detected by patient monitor's detector and therefromcommunicated to instrument. The same general process may be used tocommunicate subscription information or software or firmware upgradesfrom the key 2008 to patient monitor 2002. Once successfullycommunicated, credit or subscription information stored on memory may bedeleted or otherwise invalidated so that it may not be used again.Reverse path communication is also envisioned, for example, where theemitters of the monitor 2004 communicate signals representing patientinformation, monitor information, use information, patient data,clinical data, alarm data, or the like to the key 2008 for lateruploading to other devices for manufacturer or other review andanalysis.

In some embodiments, the key microprocessor may also be another form ofcomputing device such as a central processing unit, graphics processingunit, application-specific integrated circuit, other dedicated hardwareor programmed general purpose hardware, or any other device capable ofhandling the functions of a microprocessor or controller. The key memorymay include a random-access memory (RAM), a read-only memory (ROM), aprogrammable read-only memory (PROM), and an erasable PROM (EPROM), aFlash-EPROM, or any other memory chip or cartridge. In some embodiments,the memory may include a computer-readable media, such as a floppy disk,a flexible disk, hard disk, magnetic tape, or any other magnetic media,a CD-ROM, DVD, any other optical media, punch cards, paper tape, anyother physical media with patterns of holes.

In some embodiments, an additional detector may be used to receivephotoenergy from emitters of the sensor 2004 or any key programmingdevice, thereby providing power to the key 2008. For example, if asensor 2004 comprises a plurality of LEDs, such as, for example, four,eight, sixteen, or the like, and a plurality are activated in a mannerthan efficiently powers the key 2008. For example, duty cycles mayadvantageously be varied when powering the key as opposed to simplecommunication. Powering photocommunicative key 2008 in this way mayextend its shelf life and may eliminate the need to provide newbatteries. Alternatively, artisans will recognize from the disclosureherein a myriad of powering technologies usable for the key 2008.

Information regarding debits, credits, subscription information, patientinformation such as test results, measurement or demographic data or thelike, or upgrades may be communicated to photocommunicative key 2008 ina manner similar to that described with respect to FIG. 21 forcommunication of information between patient monitor 2002 andphotocommunicative key 2008. For example, a refill module maycommunicate debit, credit, subscription, patient, monitor or upgradeinformation. The refill module may also store usage information forlater billing to be performed based on the usage information stored onphotocommunicative key 2008. In some embodiments, billing informationmay also be sent from photocommunicative key 2008 to an informationmodule via wired or wireless interface, USB, or other communicationprotocol recognizable to an artisan as appropriate for the disclosureherein.

FIG. 23 illustrates an exemplary block diagram of the key 2008 of FIG.20. As shown in the embodiment of FIG. 23, the key 2008 includes one ormore photodiodes 2302 receiving optical signals from, for example, theemitter of the sensor 2004. These optical signals may be optionallypreprocessed with appropriate analog and/or digital circuitry 2304 toremove noise and/or boost gain and then forwarded to a microprocessor2306. To communicate back to an instrument, the microprocessor 2306 mayoptionally output signals to digital and/or analog circuitry 2310configured to drive one or more emitters 2312 that optically communicatewith, for example, the detectors of the sensor 2004. The microprocessor2306 may also advantageously communicate with a memory 2308 and acommunication device 2314. The communication device 2314 mayadvantageously comprises appropriate circuitry for USB communication,Bluetooth or other wireless communication, wired communication or thelike. As mentioned, the key 2008 may advantageously include transparentwindows allowing for the optical transmission of signals. Moreover, thewindows may be coated or shaded to reduce unwanted noise and/orinterfering wavelengths of light.

In an embodiment, the key 2008 also includes one or more additionaldetectors 2318 configured to use emitted light to acquire energy topower the key 2008. In such an embodiment, the detectors 2318communicate with a storage cell 2320 to, for example, store and regulateenergy received from the emitters of the sensor 2004. In alternativeembodiments, replaceable or other batteries may provide sufficient powerto the key 2008. In any event, the key 2008 acquires sufficient power tooperate the microprocessor 2306 and at least one of the communicationdevice 2314 and the emitters 2312 to enable communication of data, suchas, for example, credit information and other data described herein to acorresponding communication device such as the sensor 2004.

An artisan will understand from the disclosure herein that suchcommunication with the key 2008 may advantageously be between the key2008 and a monitor 2002, or between the key 2008 and a key programmingdevice, such as, for example, a refill module or the like.

FIG. 24 illustrates a simplified flow chart of a measurement refillprocess, according to an embodiment of the key 2008 of FIG. 20. In aninitial step, the key 2008 may be placed within communication proximityof a refill module, whether that is communicating through emitters anddetectors, through wired or wireless devices, USB connectivity, or thelike will at least in part dictate the specifics of the proximity of thekey to the refill device. As shown in FIG. 24, once connection isestablished with respect to the refill module, the module may refill thekey and perform accounting procedures with respect to measurements takenby certain monitors, certain accounts, certain patients, combinations ofthe same or the like. Once the key 2008 is refilled, the key is placedin proximity of the sensor 2004. As described above, the proximity mayadvantageously include a portion of mechanical mating elements aligning.

Once communication between the key 2008 and the monitor 2004 isestablished, the number of spot check measurements may advantageously beincreased on the monitor 2004. Additionally, the communication mayinclude a myriad of other one or two way exchanges of information, suchas the information described herein above.

FIG. 25 illustrates a simplified flow chart of a communication processbetween the key 2008 of FIG. 20 and a patient monitor 2004, according toan embodiment of the disclosure. For example, the key detectors 2302 maydetect light from the emitters of the monitor 2004. The light may beadvantageously organized such that some of the light providescommunication and some of the light provides power for the electronicsof the key 2008, although powering may simply be provided from anotherpower source. The key 2008 may determine whether proper handshakingprotocols have been followed and/or encryption secrets properly passed.This handshaking may include multiple back-and-forths between the key2008 and the monitor 2004. To reply to the monitor 2004, the key lightsources 2312 activate in a predetermined manner understood by themonitor 2004 to create a signal encoded with information for the key2008.

The processes, computer readable media, and systems described herein maybe performed on various types of hardware, such as hand-held devices orcomputer systems. Hand-held devices may include personal dataassistants, cell phones, portable music players, laptops, and any otherportable computing device. Computer systems and hand-held devices mayinclude a bus or other communication mechanism for communicatinginformation, and a processor coupled with the bus for processinginformation. A hand-held device or computer system may have a mainmemory, such as a random access memory or other dynamic storage device,coupled to the bus. The main memory may be used to store instructionsand temporary variables. The computer system may also include aread-only memory or other static storage device coupled to the bus forstoring static information and instructions. The hand-held device orcomputer system may also be coupled to a display, such as a CRT or LCDmonitor. Input devices may also be coupled to the computer system. Theseinput devices may include a mouse, a trackball, or cursor directionkeys. Computer systems or hand-held device described herein may includepatient monitor 2002, sensor 2004, or photocommunicative key 2008. Eachcomputer system may be implemented using one or more physical computersor computer systems or portions thereof. The instructions executed bythe hand-held device or computer system may also be read in from acomputer-readable media. The computer-readable media may be a CD, DVD,optical or magnetic disk, laserdisc, carrier wave, or any other mediathat is readable by the computer system. In some embodiments, hardwiredcircuitry may be used in place of or in combination with softwareinstructions executed by the processor.

As will be apparent, the features and attributes of the specificembodiments disclosed above may be combined in different ways to formadditional embodiments, all of which fall within the scope of thepresent disclosure. For example, the monitors of the present disclosuremay advantageously track the useful and safe life of an attached sensoror other accessory through a timing or countdown process, perhapssimilar to a reverse automobile odometer, as well as separately trackingpay-per-use or per group of use or other currency based monitoring.

Conditional language used herein, such as, among others, “can,” “could,”“might,” “may,” “e.g.,” and the like, unless specifically statedotherwise, or otherwise understood within the context as used, isgenerally intended to convey that certain embodiments include, whileother embodiments do not include, certain features, elements and/orstates. Thus, such conditional language is not generally intended toimply that features, elements and/or states are in any way required forone or more embodiments or that one or more embodiments necessarilyinclude logic for deciding, with or without author input or prompting,whether these features, elements and/or states are included or are to beperformed in any particular embodiment.

Any process descriptions, elements, or blocks in the flow diagramsdescribed herein and/or depicted in the attached figures should beunderstood as potentially representing modules, segments, or portions ofcode which include one or more executable instructions for implementingspecific logical functions or steps in the process. Alternateimplementations are included within the scope of the embodimentsdescribed herein in which elements or functions may be deleted, executedout of order from that shown or discussed, including substantiallyconcurrently or in reverse order, depending on the functionalityinvolved, as would be understood by those skilled in the art.

All of the methods and processes described above may be embodied in, andfully automated via, software code modules executed by one or moregeneral purpose computers or processors, such as those computer systemsdescribed above. The code modules may be stored in any type ofcomputer-readable media or other computer storage device. Some or all ofthe methods may alternatively be embodied in specialized computerhardware.

It should be emphasized that many variations and modifications may bemade to the above-described embodiments, the elements of which are to beunderstood as being among other acceptable examples. All suchmodifications and variations are intended to be included herein withinthe scope of this disclosure and protected by the following claims.

Although the foregoing invention has been described in terms of certainpreferred embodiments, other embodiments will be apparent to those ofordinary skill in the art from the disclosure herein. For example, whenthe electronic components of a monitor include reusable yet separableelectronics such as a Y-type sensor, those electronics may plug intoreceptacles on a key that could then have virtually any shape, includingshapes designed to minimize interfering light or other noise.Additionally, other combinations, omissions, substitutions andmodifications will be apparent to the skilled artisan in view of thedisclosure herein. Accordingly, the present invention is not intended tobe limited by the reaction of the preferred embodiments, but is to bedefined by reference to the appended claims.

Additionally, all publications, patents, and patent applicationsmentioned in this specification are herein incorporated by reference tothe same extent as if each individual publication, patent, or patentapplication was specifically and individually indicated to beincorporated by reference.

A spot check monitor credit system has been disclosed in detail inconnection with various embodiments. These embodiments are disclosed byway of examples only and are not to limit the scope of the claims thatfollow. One of ordinary skill in art will appreciate many variations andmodifications.

1. A spot check credit system partitions the task of distributing sensorcredits between a server functioning as a credit provider and aplurality of clients functioning as credit requesters, the server andclients communicate over a computer network, the server runs a webserver program so as to serve web pages to the clients, the clients runweb browsers so as to receive the web pages and access spot checkcredits, the spot check credit system comprising: a server thatcommunicates a plurality of web pages over a computer network; a clientin communications with the server and executing a web browser so as toreceive the web pages; a spot check credit request relayed from theclient to the server via one of the web pages; the request specifying asensor ID and a requested number of credits to purchase; each spot checkcredit enables a single measurement for a group of physiologicalparameters; and a credit file application that executes on the server soas to generate a credit file in response to the spot check creditrequest; the credit file is downloaded from the server to the client. 2.The spot check credit system according to claim 1 further comprising: aphysiological monitor in communications with the sensor so as to performspot check measurements in conjunction with the sensor; and the monitorin communications with the client so as to download the spot checkcredit file.
 3. The spot check credit system according to claim 2wherein the credit file comprises: a file sequence code indicating whenthe credit file was created relative to other credit files; a filesensor ID indicating a sensor; and a number of spot check credits thatwere purchased for the credit file.
 4. The spot check credit systemaccording to claim 3 wherein the sensor comprises a memory that stores:a sensor ID identifying the sensor a sequence code of the most recentcredit file used to add credits to the sensor; a spot check creditnumber that is decremented after each spot check; and the memoryreadable by the monitor so as to determine each of the sensor ID, thesequence code and the spot check credit number.
 5. The spot check creditsystem according to claim 4 wherein the monitor comprises: an interfacethat downloads the sensor memory and uploads credit file data when thesensor is plugged into the monitor; a monitor display that indicates thesensor ID, the sequence code and the spot check credit number; and aprocessor that compares the credit file with the sensor memory so as toverify the sensor ID and the sequence code.
 6. The spot check creditsystem according to claim 5 wherein the monitor communicates with theclient via at least one of a USB cable interconnecting the monitor andthe client and a memory card that can be read from and written to byboth the client and the monitor, the memory card physically transferredbetween the client and monitor for uploads and downloads.
 7. The spotcheck credit system according to claim 6 wherein the sequence code is acoordinated universal time (UTC) stamp.
 8. A spot check credit methodcomprising: specifying a sensor ID; requesting spot check credits forthe specified sensor; creating a credit file with a time stamp, thesensor ID and the credits; and encrypting the credit file.
 9. The spotcheck credit method according to claim 8 further comprising: downloadingthe credit file to a client from a server; retransmitting the creditfile to a monitor connected to the client either directly via a cableconnected between the client and monitor or indirectly via a memorycard.
 10. The spot check credit method according to claim 9 furthercomprising: decrypting the credit file; and reading a sensor attached tothe monitor so as to verify its sensor ID matches the credit file sensorID.
 11. The spot check credit method according to claim 10 furthercomprising: reading the sensor to determine a sensor time stamp;verifying that the credit file time stamp is later than the sensor timestamp; and adding the credit file credits to pre-existing sensorcredits.
 12. The spot check credit method according to claim 11 furthercomprising: performing a spot check measurement; writing a decrementedcredit count to the sensor; uploading the spot check results to theclient; and associating an email address with the spot check results.13. The spot check credit method according to claim 12 furthercomprising: uploading the spot check results and email address to theserver; storing the spot check results on a server database; andemailing the spot check results from the server to the email address.14. A spot check monitoring method attaches a reusable sensor to a spotcheck monitor so as to upload sensor credits to the sensor; each sensorcredit represents a quantum of currency; the monitor reads the number ofsensor credits and is enabled to make a physiological measurement inconjunction with the sensor if the number of sensor credits is greaterthan zero; after the measurement, the number of sensor credits aredecremented, the spot check monitoring method comprising: providing aphysiological monitor having a sensor port that attaches a reusablesensor; attaching an optical sensor to the sensor port; uploading atleast one sensor credit from the monitor to store in sensor memory, thesensor credit representing a quantum of currency; reading the sensormemory with the monitor; the monitor determining if the number of sensorcredits is at least one; the monitor performing a physiologicalmeasurement in conjunction with the sensor based upon a remaining sensorcredit; and the monitor decrementing the sensor memory correspondingwith the physiological measurement.
 15. The spot check monitoring methodaccording to claim 14 further comprising: providing a monitor buttoncorresponding to one measurement of a particular parameter; respondingto a press on the button to initiate the one measurement; and the onemeasurement corresponding to a one credit decrement of the number ofsensor credits.
 16. The spot check monitoring method according to claim15 further comprising providing a second monitor button corresponding toone measurement of a second particular parameter.
 17. The spot checkmonitoring method according to claim 16 further comprising virtualizingthe monitor button and second monitor button on a touch screen.
 18. Thespot check monitoring method according to claim 17 further comprising atimer provided on the touch screen corresponding to the time to completethe one measurement.
 19. The spot check monitoring method according toclaim 18 wherein the particular parameter corresponding to the monitorbutton is total hemoglobin.
 20. The spot check monitoring methodaccording to claim 19 wherein the second particular parameter is anabnormal hemoglobin.
 21. A photocommunicative key comprising: adetector; an emitter; a memory configured to store information forcommunication with a patient monitor; and a processor configured toprocess signals received from the detector, generate signals to be sentto the emitter, and store information in the memory, wherein theprocessor is also configured to generate a signal to be sent to thepatient monitor, the signal capable of communicating at least some ofthe information stored in the memory via the emitter and wherein atleast a portion of the information to be sent includes measurementcredits authorizing the patient monitor to make additional patientmeasurements.
 22. The photocommunicative key of claim 21, wherein thesignal also comprises software upgrades for the patient monitor.
 23. Thephotocommunicative key of claim 21, wherein the detector receives aninput signal communicating usage information relating to billing forpatient monitor usage.
 24. A method of accounting for use of a medicaldevice, the method comprising: generating a signal with amicroprocessor, said signal including credit information authorizingsaid medical device to perform additional measurements; and driving alight source in a manner responsive to said signal, said light sourceemitting optical radiation configured to be received by a detector of anoptical sensor of said medical device to authorize said device toperform some or all of that device's functions.
 25. The method of claim24, wherein said signal generated by said microprocessor includesupgrade information for said monitor.
 26. The method of claim 24,wherein said signal generated by said microprocessor includes patientinformation for said monitor.
 27. The method of claim 24, key includesnonoptical communication components.
 28. The method of claim 24, whereinsaid components comprise USB circuitry.
 29. The method of claim 24,wherein said components comprise wireless circuitry.
 30. A method ofaccounting for use of a medical device, the method comprising: receivinga signal from an electronic device other than said medical device, saidsignal including credit information authorizing said medical device toperform additional measurements, said reception comprising one ofoptical communication, wireless communication, and USB communication;and configuring said medical device to take additional measurementsconsistent with said signal.
 31. A digital device capable of authorizinga patient monitor to take measurements, the device comprising: acommunication portion configured to communicate with said patientmonitor to provide credits usable by said patient monitor to takemeasurements on a monitored patient; and a processing portion configuredto receive and send information from and to said patient monitor, saidinformation including said credits.
 32. The digital device of claim 31,wherein said communication portion includes USB circuitry.
 33. Thedigital device of claim 31, wherein said communication portion includeswireless circuitry.
 34. The digital device of claim 33, wherein saidwireless circuitry comprises Bluetooth circuitry.
 35. The digital deviceof claim 31, wherein said communication portion includes opticalcircuitry.
 36. The digital device of claim 35, wherein said opticalcircuitry communicates with complementary components associated withsaid patient monitor, said complementary components including emittersand detectors.
 37. The digital device of claim 35, wherein at least oneof said detectors powers said digital device.
 38. The digital device ofclaim 35, wherein said digital device is shaped to mechanically matewith a sensor of said medical detector.
 39. The digital device of claim35, comprising transparent windows.